WO2016008588A1

WO2016008588A1 - Heat storage device

Info

Publication number: WO2016008588A1
Application number: PCT/EP2015/001467
Authority: WO
Inventors: Heinz Posselt; Manfred Schönberger
Original assignee: Linde Aktiengesellschaft
Priority date: 2014-07-17
Filing date: 2015-07-16
Publication date: 2016-01-21
Also published as: AU2015291473A1; US20170160020A1; EP3169962A1; MA39556A1; MA39556B1; DE102014010636A1; CN106574826A

Abstract

The invention relates to a heat storage device (1) for transferring heat indirectly between a fluid (F) and a heat storing medium (P), and for storing transferred heat, comprising a container (10, 10a) that surrounds an interior (I) of said container (10, 10a), said heat storing medium (P) being located in this interior (I). According to the invention, a plurality of vertical tubes (24) are arranged in the interior (I) of the container (10, 10a), each of these tubes (24) being fluidically connected (245, 500) to a vertical header tube (25) by means of a lower end section (24b), each of said tubes (24) comprising a plurality of heat transfer fins (211), and these heat transfer fins (211) coming into contact with the heat storing medium (P).

Description

description

Wärmespeichereinrichtunq

The invention relates to a heat storage device according to claim 1. Such heat storage devices are used for indirect heat transfer between a fluid and a heat storage medium and for storing the heat transferred from the fluid to the heat storage medium.

The heat storage medium may in particular be a so-called phase change material (phase change material or PCM for short), with the aid of which the heat of a fluid, which may be any process medium or process stream, is at a nearly constant temperature can be stored or released again by means of the latent heat (eg during the liquid-solid phase transition). Due to the jump in the specific volume between the solid and liquid phases of the heat storage medium, the phase transition must be spatially continuous to avoid local pressure differences. Otherwise these pressure differences would become mechanical

Overuse of the heat transfer system between the fluid and the

Heat storage medium or phase change material lead.

Heretofore, it has been known (see, for example, KR20000033239) that pipes through which the fluid or process medium flows and which are provided with external heat transfer fins are horizontally disposed in the container accommodating the heat storage medium. Here, however, is a uniform melting or freezing of the

Heat storage medium not ensured.

Furthermore, concepts are known (cf., for example, CN 102777874), in which the tubes are guided vertically with their outer heat transfer ribs between two tubesheets. However, the lower tube plate must weigh the full weight of the heat storage medium. For large volumes of heat storage medium therefore tube plates of several meters diameter would be necessary. Proceeding from this, the present invention has the object to improve a heat storage device of the type mentioned in that the aforementioned disadvantages are at least partially reduced. This problem is solved by a heat storage device having the features of claim 1.

Advantageous embodiments of the invention are in the corresponding

Subclaims specified or will be described below.

According to claim 1, the invention provides that in the interior of the

Container is arranged a plurality of tubes, each extending along a longitudinal axis, wherein the tubes or the longitudinal axes - relative to a properly arranged heat storage device - extend along the vertical, each of the tubes at a lower end portion of the respective tube with a ( especially individual) also vertically extending

The manifold is in fluid communication (i.e., the manifold extends along a longitudinal axis that is relative to an intended one

Heat storage device along the vertical runs). The

Flow connections can e.g. in each case be formed by a pipe section or flow path running along the horizontal, which connects the respective pipe with a lower portion of the manifold or by a collector (see below). Furthermore, according to the invention, the tubes have a plurality of heat transfer ribs which contact the heat storage medium in order to ensure the best possible transfer of heat between the fluid and the heat transfer medium

To ensure heat storage medium.

The heat storage device is preferably designed to remove the fluid (e.g.

Water vapor) when storing heat in the respective tube from top to bottom, so that heat from the fluid flowing in the respective tube on the

Heat storage medium is transferable, wherein the heat storage device is further preferably designed to guide the fluid in the manifold from the bottom up again, wherein the fluid is removable in particular via the collecting tube. For storing heat, the heat storage device is preferably designed to supply the fluid (eg water) via the collecting tube from top to bottom Lead and over the pipes from the bottom up again, so that heat of the

Heat storage medium is transferable to the fluid.

Preferably, the heat transfer ribs can each protrude in the radial direction of the respective tube from a jacket of the respective tube or be fixed in any other way to the respective tube. The heat transfer ribs can also protrude in the radial direction from an additional carrier, which is fixed to a jacket of the respective tube. The carrier may itself be tubular or cupped. In particular, the respective carrier may have two shells which face each other and surround the respective sheath on which they are fixed. From the carrier or trays, the heat transfer ribs are then placed in e.g. radial direction. The heat transfer fins may be integrally formed with or otherwise bonded to the carrier (s) (e.g., welded joints).

Due to the increased by the ribs effective surface of the tubes an improved heat transfer between the fluid and the

Heat storage medium. With the heat storage device according to the invention, on the one hand, heat of a fluid or process medium can thus be transferred to the heat storage medium and stored therein or, on the other hand, heat stored in the heat storage medium can be transferred to a fluid or process medium. Due to the vertically arranged tubes, a spatially homogeneous melting or freezing of the heat storage medium around the tubes is possible, wherein in addition in addition due to the guidance of the fluid through the tubes (with recirculation or supply through a manifold), a lower tube sheet is dispensable, so that the weight of the heat storage medium does not have to be derived via a lower tube plate, but eg via a correspondingly designed container bottom. Preferably, therefore, the pipes and possibly the

Manifold and the flow connection between the pipes and the

Holding manifold from above, in particular by a distributor or a tube sheet and / or other fittings. As already mentioned, the heat storage medium is preferably a phase change material, that is, a material whose latent heat of fusion, solution heat or heat of absorption is greater than the heat which it can store due to its specific heat capacity (without phase transformation). The heat storage device is also called as

Latent heat storage device referred to. The heat storage medium may be e.g. to act a nitrate salt or the heat storage medium can

Have nitrate salt, such as NaN0 ₃ or KN0. ₃ The heat storage medium may also comprise a mixture of nitrate salts, in particular a mixture of NaNO ₃ and KNO ₃ .

For distributing the fluid to the tubes, a distributor is preferably provided, which is in fluid communication with the tubes at an upper end of the tubes, so that the fluid can be fed into the respective tube via the distributor.

According to a preferred embodiment of the invention it is provided that the distributor has at least one (in particular annular) pipeline, each having a first and a second chamber separated therefrom.

Of course, it is also possible to provide a plurality of these annular pipelines, which are then preferably arranged concentrically with one another in a plane.

According to an alternative variant of the heat storage device according to the invention, the distributor can also have a tube bottom, in which the tubes are anchored with their upper end or. The distributor can furthermore have a further tube plate in which the collecting tube is anchored.

According to an embodiment with collecting pipe for drawing off and if necessary supplying the fluid, it is preferably provided that the pipes are each anchored with an upper end in a tube bottom of the distributor, so that the fluid flows over the

Tube bottom in the respective tube can be fed (or deducted from it) and flows therein down or up. The collecting tube is preferably passed through the tube bottom with an upper end portion or a corresponding flow path leads through the tube bottom.

Furthermore, the tube plate with a preferably hood-shaped lid of the container can define a chamber of the distributor, into which the fluid via a connection piece can be introduced or from which the fluid is removable via the neck. The fluid introduced into the chamber can then enter the tubes via the tubesheet or can be withdrawn from the tubes via that chamber. The collecting tube is preferably arranged centrally in the container along the vertical, wherein the tubes are preferably arranged radially further out and are preferably distributed around the collecting tube.

According to a further embodiment of the invention, it is provided that the flow connection between the tubes and the collecting tube has a Sammier or is produced via a collector, wherein the tubes each open into the collector via a lower end opening of the respective tube, and wherein the collecting tube via a lower end opening of the manifold opens into the collector. The manifold, pipes and collector can be carried through the tubesheet.

According to one embodiment, it is provided that the collector has a convex jacket which delimits an interior of the collector for collecting the fluid, wherein in particular at least an upper region of the jacket of the collector is designed in the shape of a spherical segment. Preferably, the tubes open into this upper region of the collector, wherein preferably the collecting pipe opens at a highest point of the collector or the jacket of the collector into the collector.

Preferably, the jacket of the collector is formed cylindrically symmetrical, wherein the cylinder axis coincides with the longitudinal axis of the collecting tube, which opens from above into the collector.

According to a further preferred embodiment it is provided that the

Interior of the container for void avoidance in a solidification of the

Heat storage medium has a region surrounding the collection tube or a region in which the collection tube is arranged, wherein in the region none of the tubes is arranged. The said region preferably extends along the collecting tube. About this area (which is also referred to as a feeder), in which no or a reduced heat transfer takes place, during the solidification of the heat storage medium fluid heat storage medium in particular down and out to the pipes towards redeemed. The area preferably has one Diameter, which is at least twice as large as the outer diameter of the manifold. Preferably, the diameter of the area is further selected so that the heat storage medium is the last thing fixed here. If this is the case, the diameter may also be smaller.

Furthermore, the manifold can be performed without additional insulation. An insulation can then by the insulating effect of the (solidified)

Heat storage medium or salt can be achieved. The central region then preferably has a correspondingly larger diameter over which the desired insulation is provided.

To provide the required amount of fluid heat storage medium, the interior of the container has at the top of the tubes an area or sub-volume, e.g. adjacent to the tubesheet, and in which said amount of fluid heat storage medium is providable. In this area or

Partial volume of the interior, the tubes preferably have no heat transfer ribs.

Furthermore, it can also be provided that the tubes each have a lower portion, through which the respective tube opens into the collector, wherein no heat transfer ribs are also provided at these portions.

In all embodiments of the invention can be provided that the container is designed as an inner container, which is arranged in an inner space of an outer container, so that a gap between the jacket of the inner container and a jacket of the outer container is present.

The gap or portions of the gap may be evacuated and / or filled with an insulating material (e.g., in the form of a bed).

Furthermore, the inner container via a suspension on the jacket of the

Outer container to be hung.

Furthermore, in all embodiments at a lower region or bottom of the jacket of the container or inner container, a nozzle for feeding the Interior of the container or inner container with heat storage medium and / or be provided for removing the heat storage medium from the interior of the container or inner container. The nozzle can have a heating device, so that the heat storage medium can optionally be converted into the liquid state of matter.

Further features and advantages of the present invention will be explained in the description of exemplary embodiments with reference to the figures. Show it:

Fig. 1 is a schematic sectional view of a Ausführungsforrn a

heat storage device according to the invention;

Fig. 2 is a schematic, partial sectional view of an alternative

Embodiment of the distributor according to FIG. 1

Fig. 3A is a schematic sectional view of a tube of a

heat storage device according to the invention;

Fig. 3B is another schematic sectional view of a tube of a

heat storage device according to the invention;

Fig. 4 is a sectional view of another embodiment of a

Heat storage device according to the invention. Fig. 1 shows in connection with Fig. 3A and Fig. 3B, an embodiment of a heat storage device 1 according to the invention comprising a container 10 with a jacket 11 which defines an interior I of the container 10, wherein in the interior I, a heat storage medium P in shape a phase change material is arranged. In the interior I of the container 10, a plurality of tubes 24 are further arranged, each extending along a longitudinal axis, wherein the

Longitudinal axes relative to an intended arranged state of the heat storage device 1, parallel to the vertical z run. The tubes 24 are surrounded by the heat storage medium P and contact this, so that a run in the tubes 24 fluid F in an indirect heat transfer with the Heat storage medium P can occur. The tubes 24 are formed as shown in FIG. 3A or 3B.

Each tube 24 is adapted to guide said fluid F down the vertical z. At a lower end portion 24a, the tubes 24 are connected via a respective flow connection with a central collecting tube 25, in which the fluid F is guided upwards again. The flow connections can e.g. be formed by extending along the horizontal pipe sections 245, which connect the respective pipe 24 with a lower portion of the manifold 25.

The fluid F is then preferably introduced at an upper end 24b of the respective tube 24 by means of a distributor 35 into the respective tube 24, then flows along the vertical z or longitudinal axis in the respective tube 24 downwards and then flows through the pipe sections 245 in the Collecting tube 25 and then flows upwards again in it (the distributor 35 can also in the manner of Figure 2 as

Be formed double tube bottom, wherein the tubes 24 are anchored in the first tube sheet 310 and the manifold 25 in the further tube plate 320). In this case, the fluid F can exchange heat on its way down in the tubes 24 with the heat storage medium P. For example, the fluid F can be solid

State of aggregation heat storage medium P melt, the

Heat storage medium P comparatively much heat energy (heat of fusion) absorbs. At a later time, the heat storage medium P can be discharged if necessary by the heat storage medium P is brought to solidification, the heat storage medium P, the previously absorbed amount of heat as solidification heat back to the guided in the respective pipe 24 fluid F, which is heated accordingly.

Furthermore, the manifold 25 may have a heat insulation 253. Thus, the manifold 25 may be formed as a double tube having an inner tube 252 and an inner tube 252 surrounding the outer tube 251, wherein the heat insulation 253 may be disposed in an annular gap 254 between the inner tube 252 and the outer tube 251 of the manifold (25).

By the fact that the respective tube 24 is acted upon at the upper end 24 b with the fluid F or the fluid F again at the upper end of the collecting tube 25th is withdrawn, can be dispensed with a tube bottom at the lower end 24a of the tubes 24. The load of the heat storage medium P must therefore not be intercepted by a lower tube plate, but can in a correspondingly solidified substrate or a suitably dimensioned

Container bottom of the container 10 are introduced.

A typical cross section of a tube 24 according to the invention is shown in FIG. 3A. In this case, the respective tube 24 preferably has a cylindrical shell 2 0, protrude from the radial direction of heat transfer ribs 211, which provide an increase in the effective surface of the shell 210 of the tube 24, so that the heat transfer between the respective tube 24 and the surrounding Heat storage medium P is improved.

FIG. 3B shows a further embodiment of a tube 24 according to the invention, wherein, in contrast to FIG. 3A, the heat transfer ribs 211 are fixed to separate, cup-shaped carriers 212, 213, which are fixed in pairs to the jackets 210 of the tubes 24. In this case, the carriers 212, 213 arranged on a jacket 210 can be fixed to one another in order to realize an attachment to the respective outer tube 21. Fig. 2 shows an alternative to Fig. 1 embodiment of a manifold 35, which can be used in a heat storage device 1 of FIG. 1 instead of the manifold 35 used. The distributor 35 is designed as a double tube bottom, which has two parallel tube plates 310, 320, namely a (first) tube plate 310, in which the collecting tube 25 is anchored, and a parallel further (second) tube plate 320, in which the respective tubes 24 are anchored. In this case, a first chamber 301 is formed between the two tubesheets 310, 320, into which the liquid medium F can be introduced, so that it can pass through passage openings 3 1 of the first tube plate 310 in the respective tubes 24. Furthermore, the recycled in the collecting pipe 25 liquid phase F can be passed through through holes 321 of the further tube plate 320 in an adjacent second chamber 302, from which the liquid phase F can be deducted and fed to their further use.

FIG. 4 shows a sectional view of another inventive device

Heat storage device 1. The heat storage device 1 has a container 10a in the form of an inner container, the shell 11a of which surrounds an inner space I of the container 10a, wherein a heat storage medium P is arranged in the inner space I. The container 10a is arranged in an inner space Γ, which is bounded by a jacket 11b of an outer container 10b, so that between the inner and the outer container 10a, 10b, a gap is created, which is preferably evacuated and filled with a thermal insulation 10c , eg in the form of a bed.

The container 10a is preferably via a suspension 2 on the shell 11b of the

Outer container 10b stored or suspended. The weight of the two containers 10a, 10b is introduced into the ground via feet 13 of the outer container 10b.

For feeding the interior I of the container 10a with heat storage medium P or for removing heat storage medium P from the interior I of the container 10a, a nozzle 600 is provided, which preferably has a heater 601, so that the heat storage medium P when discharging or in the liquid state of aggregation can be maintained.

For the heat transfer with the heat storage medium P, a plurality of tubes 24 are provided in the interior I of the container 10a, each extending along the vertical z and surrounded by the heat storage medium P or contact this. The tubes 24 may in turn, as already described above, have heat transfer ribs 211 (e.g., as shown in Figures 3A and 3B without inner tubes 22).

The tubes 24 are further provided with an upper end 24b, on which the tubes 24 each have an upper, end-side opening 242, in a tube plate 401 of a

Distributor 400 of the container 10a anchored, so that the fluid F can be fed via the tube sheet 401 in the respective tube 24 and deducted from it and can be guided down or up there. In this case, the tube plate 401 bounded with an upper lid 10d of the container 10a, a chamber 404 of the distributor 400, in which the fluid F via a nozzle 405, the upper lid 11 of the d

Outer container 11 b is arranged, as well as a to the nozzle 405th

subsequent pipeline 402, which opens into the chamber 404, into the chamber 404 can be introduced. Likewise, the fluid F via the pipe 402 and the nozzle 405th are withdrawn from the chamber 404. Furthermore, the fluid F introduced into the chamber 404 can enter the tubes 24 via the tube bottom 401 or can be withdrawn from the tubes 24 via that chamber 404. At a lower end portion 24a, the tubes 24 have a front-side lower opening 241, via which the tubes 24 each open into a collector 500. The collector 500 has a jacket 501 which is cylindrically symmetrical to the longitudinal axis of the container 10a (or the collecting tube 25th , see below) and delimits an interior space I "of the collector 500, whereby an upper area 502 of the jacket 501 or of the collector 500 is formed as a spherical segment The tubes 24 open via this upper area 502 into the interior space I" of FIG Collector's 500 one.

For withdrawing the fluid F from the collector 500 or for introducing the fluid F into the collector 500, in turn, a vertical collecting pipe 25 is provided, which runs parallel to the tubes 24, in the middle in the container 10a along the vertical longitudinal axis of the container 0a, wherein the tubes 24 are preferably arranged radially further outward and are preferably grouped around the manifold 25 around. The manifold 25 has a lower end opening 250 through which the manifold 25 opens into a highest point of the collector 500. With its upper end portion 25 a, the manifold 25 through the tube sheet 401

passed and is connected to a nozzle 406 on the upper lid 1 1d of the

Outer container 11b in fluid communication through which the fluid F from the

Collecting tube 25 is removable or via which the fluid F is introduced into the collecting pipe 25. The heat storage device 1 is thus configured so that the supply and discharge of the fluid F takes place from above.

For loading the heat storage device 1 (i.e., storing heat), the fluid F, e.g. Water vapor, fed through the manifold 400, i.e., via the nozzle 405, the chamber 404, and the tubesheet 401 into the tubes 24, flows down the tubes 24, giving off heat to the thermal storage medium P, which is thereby liquefied. The cooled fluid F (e.g., cooled

Water vapor) is withdrawn via the collector 500 and the manifold 25 and the nozzle 406 again and fed to its further use. For discharging the heat storage device 1 (ie, heat storage), the fluid F (eg Water) through the nozzle 406 into the manifold 25, flows therein down into the collector 25 and is passed from this through the pipes 24 up again and withdrawn via the manifold 400. In the tubes 24, the fluid F heat of the heat storage medium P record, which can be brought to solidification.

For avoiding voids when the heat storage medium P solidifies, a central region B of the inner space I of the container 10a surrounding the collecting tube 25 is provided, in which none of the tubes 24 is arranged, so that substantially no heat transfer takes place there. About this area B fluid heat storage medium P is replenished during solidification of the heat storage medium P. A quantity of fluid heat storage medium P required for this purpose is provided in a partial volume V of the interior I of the container 10 a at the upper end 24 b of the tubes 24. In this region or partial volume V of the inner space i, the tubes 24 preferably have no heat transfer ribs 211 in order to reduce the heat transfer here. The partial volume V is marked by the two water levels P 'and P ". The solid, solidified heat storage medium P has the lower one

Level P 'on; Furthermore, the tubes 24 each have no heat transfer ribs 211 at the lower end portion 24a through which the tubes 24 lead into the collector 25. These lower end portions 24a of the tubes 24 may further have a curvature or have a bent course, so that the tubes 24 can each open vertically into the jacket 501 of the collector 500.

reference numeral

1 heat storage device or latent heat storage

10, 10 a container, in particular inner container

10b outer container

10d, 11d cover

1 1, 11 a, 11 b coat

12 suspension

13 feet

25a lower end

24b upper end

251 outer tube

252 inner tube

254 annular gap

24 pipe

24a lower end section

25 manifold

25a upper end section

35, 300, 400 distributors

31 Annular piping

32 First Chamber

33 Second Chamber

210, 240 coat

211 heat transfer ribs

212, 213 carriers

220, 250, 241 Lower front opening

221, 242 Upper front opening

222, 253, 10c thermal insulation

245 pipe section or flow connection

301 First Chamber

302 Second Chamber

310, 401 tube sheet

311 passage opening

320 more tubesheet

321 passage opening 402 pipeline

404 chamber

405, 406, 600 nozzles

500 collectors

501 coat

502 Upper area

B Free area

I, Ι ', I "interior

F fluid

P heat storage medium p. pn level

V volume

z vertical

Claims

claims

1. heat storage device (1) for indirect heat transfer between a fluid (F) and a heat storage medium (P) and for storage

transferred heat, with:

- A container (10, 10 a) surrounding an interior space (I) of the container (10, 10 a), wherein the heat storage medium (P) in the interior (I) is arranged, characterized in that in the interior (I) of the container (10, 10a) a plurality of vertical tubes (24) is arranged, wherein the tubes (24) are each surrounded by the heat storage medium (P), wherein the tubes (24) each have a lower end portion (24b) with a vertical manifold (25) are in fluid communication (245, 500), wherein the tubes (24) each having a plurality of heat transfer ribs (21 1), wherein the heat transfer ribs (211) contact the heat storage medium (P).

2. Heat storage device according to claim 1, characterized in that the heat storage medium (P) is a phase change material.

3. Heat storage device according to one of the preceding claims, characterized in that the fluid (F) can be guided in the tubes in both flow directions.

4. Heat storage device according to one of the preceding claims, characterized in that the tubes (24) in each case at an upper end (24b) with a distributor (35, 400) are in fluid communication, so that the fluid (F) via the distributor (300 , 400) in the respective tube 24) can be fed.

5. Heat storage device according to claim 4, characterized in that the distributor (400) has a tube plate in which the tubes (24) are anchored.

6. heat storage device according to claim 4 or 5, characterized in that the distributor (400) has a further tube sheet, in which the

Collecting tube (25) are anchored.

7. Heat storage device according to one of the preceding claims, characterized in that the collecting tube (25) is arranged centrally in the container (10), wherein the tubes (24) are arranged distributed around the collecting tube (25).

8. Heat storage device according to one of the preceding claims, characterized in that the collecting tube (25) has a heat insulation (253), wherein in particular the collecting tube (25) is designed as a double tube having an inner tube (252) and the inner tube (252 ), wherein the heat insulation (253) in an annular gap (254) between the inner tube (252) and the outer tube (251) of the collecting tube (25) is arranged.

9. Heat storage device according to one of the preceding claims, characterized in that the flow connection between the tubes (24) and the collecting tube (25) has a collector (500), wherein the tubes (24) each have a lower opening (241) of the respective Pipe (24) into the collector (500) open, and wherein the collecting tube (25) via a lower opening (250) of the

Collecting tube (25) opens into the collector (500).

10. A heat storage device according to claim 9, characterized in that the collector (500) has a convex jacket (501) which defines an interior space (I ") of the collector (500), wherein in particular at least one upper region

(502) of the jacket (501) of the collector (500) is formed spherical segment.

1 1. A heat storage device according to one of the preceding claims, characterized in that the interior (I) for Lunkervermeidung in a

Solidifying the heat storage medium (P) of the container (10, 10 a) a

Has collecting tube (25) surrounding area (B), in which none of the tubes (20, 24) is arranged.